## What is the crystal structure of CsCl?

CsCl has a cubic structure that consists of an infinite chain of ions. The Cs (or Cl) ions sit at the eight corners of the cube and the Cl (or Cs) sit at the center of the cube (thus it is NOT a body-centered lattice since that requires the SAME ion to occupy the edges and center).

## Which of the following solids is the structure of CsCl Crystal?

In case of CsCl, the Cs stays at the centre and is surrounded by 8 Cl atoms which form Body centred cubic structure. So, the answer to this question is A. Body centred cubic structure.

## How are atoms arranged in a crystal structure?

Crystals are formed by stacking the molecules. The β-rhombohedral structure of boron has seven of these icosahedral molecules in each unit cell, giving a total of 84 atoms. Molecules of sulfur are usually arranged in rings; the most common ring has eight atoms.

## How many atoms are present at each of these types of positions in a body-centered cubic unit cell?

The face-centered cubic (fcc) has a coordination number of 12 and contains 4 atoms per unit cell. The body-centered cubic (bcc) has a coordination number of 8 and contains 2 atoms per unit cell. The simple cubic has a coordination number of 6 and contains 1 atom per unit cell.

4 atoms

## How many atoms are present in per unit cell of BCC?

Number of Atoms in BCC Cell: 8 corners × 1/8 per corner atom = 8 × 1/8 = 1 atom.

## Why is BCC not close packed?

BCC structures have no close packed planes. Its coordination number is just the number of equidistant neighbors from the atom in the center of the unit cell. BCC coordination number is therefore 8, as each cube corner atom is the nearest neighbor.

## Where are tetrahedral voids located in FCC?

In a FCC structure, one corner sphere and three face spheres form one tetrahedral void. In a FCC structure, two tetrahedral voids are obtained along one cube diagonal. There are a total of four cube diagonals in one unit cell. Thus, overall, there are eight tetrahedral voids in a FCC structure.

## Where are octahedral voids located?

Other than the body center there is one of the octahedral voids at the center of each of the 12 edges Which is surrounded by 6 atoms, four belonging to the same unit cell and two belonging to two other adjacent unit cells.

## What is the difference between tetrahedral void and octahedral void?

Tetrahedral void is a simple triangular void in a crystal and is surrounded by four spheres arranged tetrahedrally around it. On the other hand, an octahedral void is a double triangular void with one triangle vertex upwards and the other triangle vertex downwards and is surrounded by six spheres.